Detailed research concerning the issue fluency, specifically relating to pauses, mean length runs, and fluency rates in Japanese EFL learners, is limited. Furthermore, the issue of tracking fluency gains has often been ignored, misunderstood or minimized in EFL educational research. The present study, which is based on six monologues conducted over a school year (2010-2011), focuses on changes in fluency and accuracy concerning students' use of the simple past and present perfect, present perfect progressive, and past perfect verb tenses. Based on the results of a university placement exam, twenty students were selected. Two groups of ten students with the highest and lowest scores were interviewed for period of six months, three times in each school semester. Research aims focus on whether or not there are changes in pausing (duration and frequency), mean length runs, fluency rates and grammatical accuracy between the two groups over the school year. Students were then videotaped concerning how they responded to different questions, which concerned students' past experiences, and views. Results, based on the transcripts of the student monologues, indicated that there was significant improvement relating to the mean length runs, and on one fluency rate, but there were no significant differences in grammatical errors either in percentage of error free clauses or in errors per 100 words between the two groups. The findings help to further our understanding of specific language gains as it relates to fluency and grammatical accuracy in students' unrehearsed speech over a school year.